Pneumatic hammer.



No. 814,306. PATBNTBD MAR. 6, 1906. A. LBVBDAHL.

PNBUMATIC HAMMER.

APPLIUATIOH FILED 1.136,27, 1904.

3 SHEETS-SHEET 1.

M@ E l mZf/eda i@ Q wm @y fw@ WW Eil/62am?? PATENTED MAR. 6, 17906.

A. LEVEDAHL.

PNEUMATIG HAMMER.

APPLIGATION rum AUG. 27. 19m.

mms

No. 814,306. Y PATBNTBD MAR. 6, 1906. A. LBVEDHL. PNEUMATIG HAMMER.

APPLICATION .FILED AUG. 2?, i904.

3 SHEETS-SHEET 34 mvv c@ WQ 00%@ C? y@ .a @www UNITED STATES PATENT OFFICEr AXEL LEVEDAHL, OF AURORA, ILLINOIS, ASSIGNOR TO AURORA AUTOMATIC MACHINERY COMPANY, OF AURORA, ILLINOIS, A

CORPORATION OF ILLINOIS. Y

,PNEUMATC HAMMER.

Specicationlof Le tters Patent.

Patented March 6, 1906.

Appiieinn ne angie 27.1904'. semi No. 222,455.

To @ZJ whom t may concern:

Be it known that I; AXEL LnVEDAHna citizen of the United States, residi at Aurora, in the county of Kane and-State o Illinois, have invented certain new and useiul Improvementsin Pneumatic Hammers; and I do hereby declare that the followin is a lull, clear, and exact description thereo reference being had to the accompanying drawings, and to theletters of reference marked thereomwhich form a part of this specification.

This invention relates to a pneumatic tool in the nature' of a portabiepneumatic hammer or device of that kind embracing a barrel or cy nder, a piston or plunger adapted to slide endwise therein, and a controlling-valve through which air or other fluid under pressure'is admitted. to and permitted-to escape from oppesiteends ofthe cylinder to give re ciprocetory movement-to the yplunger in thebarrel.

The tool illustrated in theeccompanying drawings is designed'for use -as a rivetingof construchammer; but the same features tion illustrated in s'aid ydrawings and herein claimed mayl be emplo ed in a tool used for other purposes, as for chipping and the like. e invention consists 1n the matters hereinafter' described, and pointed' out in the .appended claims.

'As shown in the drawin Figure 1 isa View in central longitudine ysection of a tool ernbodying'my invention taken through the central axes of thebanei and throttle-vaine and transversely through the controllingvalve. Fig.2 1s a like section showinga changed position of the View in central lo 'tudinal .section o1 'the i banel of the tool with the handle attached thereto, but with parts therein removed,L taken on the. line 3 3 of Fig. 1, Figa 4 is a view in cross-section of the barrel and controlling-valve, taken thro h the centralaxis he valve-casing and s owing the vaivepi tons in elevation, said section being taken u n the line'4 4 of Fig. 1. Fig. y5 is a section li eFig. 4, showing a changed position of the valve-pistons and the latter in section. Fig. 6 is a View in side elevation of the valve-bushing.` Fi s. 7, 8, 9, 10, l1, and I2 are crosssectiona views of the `vaivie-bushing. and valveistons with the surrounding parts of thevalfe-csiiig, taken on the lines 7 7, 8 8,

for contact therewith or the partei -3 is al 9 o,1o1o,111'1,and12 120i Fig. 6. Fi .13 is a detail section taken on line 13 13 of Fig. 1. Fig 14 is a detail section taken on line 14 14 of ig. 1. Fig.4 15 is a detail face view of the split thimhle and clamping-sleeve andonut s iown in Figs. 1 and 2.

In the preferred form of tool illustrated in the accompanying drawings, A indicates the working cylinder or barrel of the tool, `B the slidin piston onplunger therein, and C a handie wich is attached to the inner endor hase of thebarrel.

I) indicates the bushing of the controlling- `valve. which is located within a cylindric recess or bore formedv in a valve-casing Aa, which is located nearthe innenend or base of the barrel andcast integral therewith. The said controllin -yalve is arrangedWith its'v cent1-alanis at right an Iles to the central airis ofthe tool and erpenicullar tothe plane' of the handie 6P. hejnterior ortho bushing D constitutes a .valve-chamber in which is'lo 'cated tWovalvd-pistos E and F' which are adapted` to sfide end-wise 'in the bushing and Which'form in connection with rts andrecasses infsaisjl Bushin the `contro ng-valve G is a riveting-too of common type which i's provided with a shank Gr', that passes tln'ongli Vand is 'guided in a guide-passage atA the outer end of 4the bai-rel and the inner end of which projects into ythe barrel in iosiition pluri erV .The said shank G` of the .tool G is re meter between its ends to form a Wide and sballo-W annular groove g, which receives a s dit 'ging g', adapted dIuced part of the shank and G', pass e of the barrel. tool While permitting necessary endwise reciprocatory movement thereof: y

The plunger B is exteriorly smooth or cylindric and 1s providedV in its rear. end with a toiit'in agroove formed in the inner surface-0f theuide- 'The ring g hol s the om' disengagement from the barrel,

recess or cavity extending nearly to the for. Y

ward end of the plunger and which is preferably made ofte ered form. The rear end of the barreiA is c osed by Ineansof an end fall shaped to form an air-displacmg promotion H,which rog'ects into the barrel and conforms near y to the shape of the cavit in the rea. end of the plunger, so that 1t w1 l praetically fill said cavity in the plunger when the pensate latter is at the inward limit of its stroke, and thereby afford a minimum clearance space or areain the inner end of the barrel.

In the preferred form of construction illustrated in the accompanyin drawings the bore of the barrel A extends tghrou h the rear end of the barrel and the air-disp acing projection H has the form of a hollow body or shell, the open bore of which is inserted and secured within the end of the bore of the barrel, so as to close the latter and form the inner or rear end wall thereof. The hollow interior of the shell H thus constructed is utilized to form an air-chamber, the rear wall of which is formed by a disk or plate H', which makes a tight joint with and closes the open end of said shell H. Said disk H is inserted and secured in the end of the bore of the barrel in contact with the rear margin of the shell H, The air-chamber so formed by the shell H, and disk H is in communication with the air-supply passage by which air is sup lied to the valve-chamber of the control in -valve and contains a reserve quantity o? air under pressure desi ned to cornfor any momentary de eiency in the air-supply through the feed pipe or bore.

As a means for connecting the handle C with the inner end or base of the barrel A, said barrel is shown as provided with two outwardly and rearwardl extendin integral arms A A, arranged ob iquely witi res ect to the central axis of the barrel and W ich are engaged with obliquely-arranged sockets C C2 on the ends of the said handle." Said arms are referably made exteriorly c lindric. The soc et C is split and its` p rts are clamped together and around the arrn A by means of clam bolts c c, as seen in'p ig. 14. The socket C2 is formed in part by the metal of the handle itself and in part by a separate removable section (shown as having the form of a block c) made concaveV on its lnner face and inserted between arallel lateral extensions of the socket an held in place therein by means of a bolt c2, inserted through the b ook and the parallel lateral extension of the socket. The socket C2 is so made with a separable part in order to enable the oblique arms'A Az to be inserted in the obli ue sockets. When assembling the arts, t e block c is removed, when both soc ets ma be engaged with the arms, and the said block is l then inserted and clamped in place by the bolt c2, which also acts to ti hten the socket C2 around said arm Az. Sai' arm A is made tubular and constitutes the air inlet' or supply passage of the tool, bein adaptedy at its outer end for connection wit a4 hose oi" airsupply pipe. Said arm A', moreover, contals parts constituting a' throttle-valve, Aas Will'behereinafter described; g

y communicates with a recess or chamber` c imma` the wan 'of the bami adjacent a rllhe inner end' f of th'ej Bore of the'said projection A 1 which is luse of the clamping device the valve-casing A2 and which forms part of the air-supply passag and is in open communication with the central part of the controllinl -valve chamber. Said recess or chamber a/ 1s connected with the air-chamber formed by the hollow projection or wheel H within the base of the barrel by a passage h. extending through the bore portion of said shell and the adjacent part of the wall of the barrel.

Now referring to the means by which the said shell H and the disk l1 are secured within the inner end of the barrel A, these parts are made as follows: The bore of the barrel A, as hereinbefore stated, is extended through the inner or rear end of the said barrel7 and the latter is rovided near said inner end of the barrel with a conical bearin -surface a2, Fi 3, which is tapered outwar ly from the cy indric bore of the barrel and also between the said tapered surface c2 and the inner end of the barrel with internal screw-threads a3.

The inner end of the shell H is enlarged and made conical on its outer surface to fit the bearing-surface c. The disk H', hereinbefore referred to, which closes the inner end of the shell H, is fiat and circular and fits Within the end of the barrel, with its margin in contact with the inner end or base of the said shell H. I is a screw threaded thimble which is inserted in the end of the barrel and has external screw threads engaging the screw-threads a?, said thimble being adapted to bear at its inner edge against the plate H', so as to clamp said plate firmly against the inner margin of the hollow plug H and to alsoI clamp or force the conical surface'of the plug into close contact with the conical seat a2. Said thimble I, Fig. 15, is split or severed at one oint to make it expansible and is provideg with oppositely-inclined interior conical surfaces t t. Within the said thimble I and projecting from the outer end thereof is a tube or sleeve J, having at its inner end an exterior conical surface adapted to fit the interior conical surface t of the thimble I. The outer end of said sleeve J is made cylindric and screw-threaded and is surrounded by a ring or nut J', having at its inner end a conical exterior surface to fit the conical surface i of the thimble I. Said nut also has at its outer end a fiat-sided fian e by which it may be turned. When the t imble l is screwed into the inner end of the barrel and brought into bearing against the edge of the plate H', the nut J may then be tightened on the sleeve J, so as to draw the conical surfaces of the said sleeve and nut into the conical bearing-surfaces 'i 'i' of said sleeve, thereby expanding the thimble Within the barrel and rigidly clam ing or holding said sleeve in place. Possi ility of the loosening of these parts through the jarring of the tool due to the action of the reciprocating plunger is by the descrlbed entirely avoided.4

ISO

New referring to, the features of construction in the controlling-valve illustrated in the accompanying drawings, the bushing D of said valve is generally of cylindric form and is contained within a cylindric bore or passage extending through the valve-casing As transversely of the barrel adjacent to the tu bular arm A, which constitutes the air-su ply passa e of the tool. The interior of t e io said tubu ar bushing Dconstitutes the valvechamber, which is closed at its ends by means of 'end plates or disks D D', that are somewhat larger in diameter than the-adjacent ends ofthe valvechamber and are fitted at their margins in rabbets or annular recesses formed in the bushing around the ends of said valve-chamber. The bushing is held inplace in the'said `bore or assage of the barrel `by means of two thimb es K K, which enter the zo opposite ends of the said bore or passage and 3o scribed, and are provided with 4o collars L Ignrovide means for expandin 5o closely t have 'screw-threaded en a ement therewith. VThe inner edges of the sai t imbles are adapted to bear against the marginal parts ci the cap-plates D D', so as to press the same firmly against theV ends of the bnshi and at the same time to hold the bushing om endwise .movement Said thimbles K K are transversely split or severed to make them expansible, as inthe thimble' I, hereinbefore deolppositel k Wit inclined conical bearing-surfaces in said thimbies are located sleeves L L, having inner conical ports adapted to engage the inner conical bearing-surfaces is of the thimbles and screw-threaded Yat their outenends to receive annular collars -or nuts L', which are provided with conical ports adapted to engage inner conical bearing-surfaces 1c k of said thimbles K. Said conical sleeves L arllld t e thimbles K into binding contact wit the surrounding wall of the transverse bore or passage of the barrel. The said bushing D 1s provided at its ends with outwardly-extending annular parts or flanges d d and between its ends with like annular ribs or flanges d2 da, which ribs or flanges have the same external diameter as the interior of the bore'or gassage of the' valve-casing and fit erein when the bushing is in place in saidbore. The said bushing is also pro: vided at opposite sides thereof with longitudinal ribs d* d5, Fi s. 1 and 6, which extend between the izibs d d d and form therewith 55. in the outer surface of the bushing six approximately semicircular de ressions or recesses, which when the bus `ng is `in piace `within the transverse bore of the valve-casing constitute, with the surroundin parts of the said casing, admission and ex aust chambers adapted to communicate with orts and passages formed in the casting w 'circonstitutes the barrel andvalve-casin The air-admission passage e', formed int ve base part of the barrel at the inner end of the airsupply passage, as hereinbefore described,

opens into the central I,art of the said transverse bore or chamber of the valve-casing, and said barrel is provided with an inlet and exhaust port Rz, which opens through the wall or barrel at the inner end thereof and communicates also with the central part of said transverse bore. .An exhaust-port S2 extends 'from the inner face of the barrel near its rear end into lone' end of the said bore of the valve-casing, and exhaust and admission passages M M M extend longitudinally thrcu h the wall of the barrel and are connecte with the outer end of the same by ports m'm m, Fig. 3, said passages M M M bemg connected with the interior oi said bore near the end of the same opposite that at which the exhaustport S2 -is located. As clearly seen in Figs. 1 and 2, the bushing D is placed in said transverse bore in such manner that one oi' the external longitudinal flanges d4 on the bushin comes in contact with the inner surface of t 1e bore between the opening a and the exhaust-port R, while the lon itudinal ribd at the opposite side voi" the bus `ng cornes in contact with the diametrically Aopposite surface' of said bore. The circumferential and 'longitudinal ribs or flanges on the bushing D form at Ithe external si e of thebushing orthat'adjacent to the air# supply assa e between the said'biishing and the'wa of t e valve-casing three spaces cr chambers, as folowsz'betwen the 'ribs' d d an exhaustchamber N ,f between -the ribsd d a sup ly-chaniber G, arid' between the ribs d2 and alE anl exhanstmhamberl. Likewise at' the inner side of the busbin or that adjacent to the bore of the barrel, t e space between the ribs d and d constitutes a supply and exhaust chamber Q, the space between the-ribs d and d constitutes an admission-chamber 'R, while the spacebetween the ribs d2 and d5 constitutes an exhaust-chambers. The exhaust-chambers N and P adiacent to the end ofthe bushin at the outer side thereof coinmunicate with the outer air by means of exhaust orten and p', formed in the wall of the valira-casing. The admission and exhasst chamber Q, formed at the inner side of the bushing at one end thereof, communicates Vwith the longitudinal exhaust and admission passages M M M, leading to the outer end of the barrel A. The intermediate chamber R at the inner side of the bushing is in communication with the admission-port R', leading to the interior of the inner end of the said barrel and communicates with a central assage R in the bushing, which, in effect, ivides the valve chamber therein into two separatechambers or valve-seats, each of which contains one ofthe valve-pistons E and F. The exhaust-chamber S communicates with the interior of the barrel by`the exhaust-port Si. The said bushing D is provided between the external ribs thereon with transverse1y-ar IOS ranged slots or openings forming valve-ports and within the interlor or valve-chamber thereof with annular grooves or recesses, forming admission and exhaust passages, as follows: At the outer side of the bushing between the ribs d d' is a port n, which opens from the chamber N into an interior annular recess N'. Between the ribs d and d2 and opening from the chamber O are two ports o o', which open into annular interior recesses O' O2, located at opposite sides of the central passage R. Between the ribs d? and d3 is a port p, which opens ,from the chamber P into an interior annular recess P'. At the inner side of the said bushing D between the ribs d and. d is a port q, which opens 4from the chamber Q into an annular recess Q'. Between the annular ribs d and. cl2 is located the central space or passage R', which extends into the bushing between the inner ends of the piston-valves E and F. Between the ribs d2 and d'd is formed a port s, which opens lfrom the chamber S into an interior annular recess S.

The valve-piston E has an intermediate reduced part or neck and at its inner end a cylindric flan e e, which fits or slides in a valveseat forme in the valve-chamber adjacent to the central recess R and in which is formed the annular recess O', over or past which the yflange e moves in the shifting of the valveiston. Said valve-piston E is provided at its outer end with an enlarged cylindric part e', which lits and slides in a cylindric seat formed in the outer end of the valve-chamber exterior to the groove M. On said piston E, between the enlar ed parts e and e is a circular flange e2, whic fits the inner surface of the bushing between the'grooves N and 0'. WVhen said valve-piston E is at the inner limit of its movement, as seen in Fig. 4 the flange e is interposed between the central recess R' and the groove 0', and said groove O is then cut off from the central admissionspace R', but is in communication with the recess Q and the inlet and exhaust passages M M M, while the flange ez on said valve-piston is at this time between the grooves N and O' and cuts off communication between the exhaust-chamber Q and the said passages M M M. When the valve-piston E 1s at the outward limit of its movement, as shown in Fig. 5, the flange e stands between the grooves O and Q', thereby cutting oil` connection between the recess Q'and the admission-recess O' and leavingo en communication between the groove O' an the central admission-recess R', while the iange e2 stands outside of the eX- haust-recess N and establishes free communication between the said recess N and the passages M M M through the chamber Q and recess Q'.

The valve-piston F has a reduced intermediate part or neck and is rovided at its inner end with an enlarged cy indric part f, which ts and slides in a seat formed 1n the valvechamber at either side of the annular recess 02. At its outer end said piston F is provided with a flange f which fits and slides in a c rlindric seat formed in the adjacent outer en of the valve-chamber outside of the annular recess S. Said valve-piston F is also provided with an intermediate annular flange f2, adapted to fit the valve-chamber between the annular recesses P and S'. When the said piston F is at the inward limit of its movement, as seen in Fig. 4, the enlar ed inner part f thereof covers the groove 2 and cuts oil communication between the same and the central recess R', while the intermediate flange f2 is at some distance from the annular rib on the wall of the valve-chamber between the recesses P and SZ, and thereby leaves free communication between the said recesses and establishes connection bctween the exhaust-port S2 and exhaust-chamber P. When the said valve-piston F is at the outward limit 'of its movement, as seen in Fig. 5, its inner end stands outside of the recess'Ol, and thereby leaves the same in free communication with the central admissionpassage R', while the intermediate, flange f 2 meets the wall of the valve-chamber between the grooves P and S', and thereby cuts off communication between the exhaust-chamber P and exhaust-port S2 and chamber S.

The space at the end of the valve-chamber between the valve-piston E and the adjacent outer end of the chamber is connected by means of a port or passage t, formed by the late D', the end vof the bushing, and the ad- ]acent wall of the barrel, with a lon itudinal passage T in the wall4 of the barre, which opens thereinto through orts t t", located between the ends of said barrel.` The space at the opposite end of the said valve-chamber between the outer end of the piston F and the adj acentend, of the chamber is connected by a port u, formed in the plate D', the end portion of the bushing and adjacent part of the barrel with al longitudinal passa eA U in said barrel, which opens into sai barrel through ports u a, located at the same distances from the inner end of the barrel as the ports t t2. Said ports t t2 and u u are so arranged in the barrel that when the plunger B is at the outward limit of its movement the ports t and u' will be uncovered and in communication with' the interior of the barrel at its inner end, and when said plunger is at i the inward limit of its movement the ports t" a will be uncovered and in communication with the interior of the barrel at its outer end. The barrel is also rovided with two exhaustports a3 a3, located at such distance from the outer end of the barrel that they will be closed when the plunger is at the outer limit of its IOO movement, but will be open when the piston i is at the inner limit of its movement.

The'operation of the valve described 1s as follows: Air under pressure s admitted-from the 'throttle-valve througliihe as'sage a' to the central admission-chamber at the outer side of the valve-bushing. As shown in Figs.

been uncovered by the inner end of the pluner in its outward movement live air in the inner end of the barrel will pass through the passages T U to the said outer ends 'of the valve-chamber. The said valve-pistons E and F'being in their inward positions or adjacent to each other and the plunger being ready to start in its return or inward movement, air passes from thechamher 0 through the port o to the annular recess O', and thence to the recess Q and chamber Qr and through the passages M M M to the outer end of the barrel, in which it acts to force the plungers inyvardly. In the backward movement ofthe piston exhaust-air passes throu h the port s? to the chamber S and throu h t e port s and recess S to the recess P an then outwardly through the chamber P andexhaust-port p to the outer air` The exhaustort S2 bein located atl some distance from ,t e inner en YR" to the chamber.

of the barrel, as soon as the plunger passes said port S2 in its inward movement the airis compressed in the inner end of the barrel and the compressed air asses through the port and central recess R' and acts on the ad'acent orinner. ends of the tvvo valve-pistons and F to throw the same outward. In the outward movement of the valve-pistons air from the ends of the' valveh the passages T and U and ports t u', vifhic latter ports, as

AWell as the exhaust-ports as'aa-in the barrel, :will be uncovered by the plunger as it moves inwardly, with the result that the ports t? t will be brought into communication with the ports a? as andthrough the' same with the outer air. When theplung'er hasfreached 5 withthe valve-pistons at the-outwardlimits of their strokes,'and air fordriving the' lun the inward limit of its movement, the parts vvlll bein the position shown in" Figs. 2 and 5,

er outwardly will then enter from the c amr 0 through the'ports o o andrecesses` O OI to theentral passage R', and thence throulgh the chamber `R to the admissionport 3. At this time entrance of live air to the outer end of the barrel will be prevented by the flange e, whichv will be interposed between the recess O and the recess L', while the exhaust from the said outer en( of the barrel Will pass from the passa es M M M through the port g, the recess Q the recess `N', the vport n, and chamber N to the exhaunt-port n.

By arranging the .yalv'e-pistons as described, so t at each piston controls a sepa- .ra'te inlet-port admitting air to the inner end of theylinder, a large air-su ply is'alorded to drive the plu er outwar mits-werking stroke; while eac valve-piston has a relatively short stroke and correspondingly quick action in opening the inlet-port.

oblique arm A of the rbarrel is shaped to form a seat for a valve-bushing V, provided with an interior outwardly-facin conical valve-seat fu. Said bushing is held mits seat within the arm A bv means of a thimble W, having screw-threaded engagement with the interior of the arm A and shaped to bear at vits inner end a ainst the outer end of said bushin V, Wh1ch latter has a conical or taperedr interior bearing-surface engaging a Vta ered external surface on the inner end of said thimble. Within the bushing V is located a valve-disk` X, adapted for contact with the outwardly-facing valve-seat o. Said valve-disk'is mounted on a valve-stem X', which extends inward] and outwardly from the disk. Said stem slides at its inner end in a guide-ring o', which is su ported centrally at the inner end of the gushing V The outer end of said stem slides in a guide-ring w, which is sup orted centrally at the inner end of the thim le W, A. coiled spring W is interposed between the eide-ring w and the outer face of the said vaFve-disk and tends to hold the said valve-disk against its seat. For operating the said .throttle-valve an actuat- ICO ing-lever Y is pivoted to the end of the handle C! adjacent to the arm A', by means of a pivotin y, which passes through a flattened arm on said actuating-lever. Said arm Y passes through a slot. f'ormed in the base of the handle and opening into a guidepassa e y which is formed in the arm A, paral el with the central a'xis' of the throttle-valve.

Said guide-passage contains an rendwise-m-ovmg rod or p ungen-Y; The inner end of said 'plunger `acts on a rocking lever X2, which isl pivotally supported by a transverse pivot :n

and 1s engaged aaits outer end by said plunger .Yand at its inner end bears against the 'inner end' of the valve-stem X.

The spring W holds the' valve-disk V against its seat, and the valve is opened by pressure of the hand on the actuating-lever by which th'e same is thrown outwardly and the plunger Y` moved inwardlyy so as to actuate the lever X, and thereby throw out- Wardly the valve-istem and carry the disk away from the valve-seat.

As hereinbefore described, an air-chamber Vis formed by the .hollow interior of' the plug H ,which is in communication with the air-supply passage through thepassage h at a point inside the throttle-valve. The air contained in said air-chamber being under a compression equal to that. of the maximum pressure supplied through the hose or supply-pipe, areservcd supply of air under pressure is provided by which an ample supply of air is afforded to provide for the rapid admission which will arise from the use of two valvepistons having short strokes and consequent quick action. Inother Words, the airchamber ives an additional supply of air called for y quick admission without using a large hose.

An important feature of the invention lies in the construction of the plungers, whereby the same is made of large diameter and lighti in Weight and has a high velocity with a short stroke. l

The tool described possesses in its entirety the features of a large diameter of barrel and quick admission of air for driving the plunger forward by reason of having the two admission controlling valve pistons, which are light and have correspondingly-quick movement, with the result that each stroke given by the lunger will be as hard as that which would e given b a plunger with a longer stroke, while at t e same time the plunger will move with great rapidity and give frequent strokes, thus making the tool as awhole more effective in action.

I claim as my invention- 1. The combination with a barrel, of a plunger therein, an air-supply ipe, afthrottlc-valve, and a controlling-va ve actinor to control the supply of air to both ends ofp the barrel, said barrel being provided with an airchamber in communication by a branch passage with the air supply passa e between the throttle-valve and the controling-valve, said air-chamber being ladapted to contain a reserve quantity of air under ressure in volume sufficient to compensate or any momentary deficiency in the air-su ply.

2. The combination wit a barrel, of a plunger therein, and a controlling valve, said plunger havinr a cavity or recess in its inner end and the barrel having at its inner end an .air-dis lacing (projection, said projection being ho low an forming an air-chamber which is in communication with the airsupply passa lre` outside of the controllingvalve and is a apted to contain a reserve supply of air under pressure sufficient in quantity to compensate for momentary deficiency in the air-supply.

3. The combination with a barrel, of a plunger therein, provided with a recess or cavity in its inner end, a controlling-valve, the barrel being provided at its inner` end with an inwardly-projecting shell which closes i said inner end of the barrel and forms an airdisplacing pro'ection,l said shell also constituting part o an air-chamber which is in communication with the air-supply passage outside of the controlling-valve and is adapted to contain a reserve uantity of air under pressure sufficient in vdlume to compensate for momentary deficiency in the air-supply from the air-supply passage.

4. The combination with a barrel, of a plunger therein provided with a recess er cavit at its inner end,and a controlling-valve, said arrel being provided at its inner end with an inwardly-projecting shell, the base of which is located and secured Within the inner end of the barrel, a disk or plate closing the inner end of said shell and means for securing said 'shell and said disk or plate in place within'the barrel, said shell and disk forming an air-chamber which is in communication with the air-supply assage outside of the controlling-valve and) which is adapted to contain a reserve quantity of air under pressure desi ned to com ensate for any momentar eficiency in t e supply of air `to the control ing-valve.

5. The combination with a barrel, of a plunger therein provided with arecess or cavity in its inner end, a shell which closes the inner end of the bore of the barrel and fits at its base in the bore of the same, and means for securing the said shell in the barrel comprising a split thimble having screw-threaded engagement with the. bore ofthe barrel, a sleeve having an exterior conical sur-face en- Y gagin an interior conical surface on the thimb e, and a nut having screw-threaded engagement with the sleeve and provided with a conical surface engaging an interior conical surface on the said thimble.

6. The combination with a barrel, of a plunger therein provided with a 'recess or cavity in its inner end, a shell which closes the said inner end of the barrel and projects into said cavity when the plunger is at the inward limit of its movement, the base of said shell being located and secured within the bore of the barrel, a disk or plate located within the bore of the barrel in contact with said inner end of said shell and means for clampin said shell and said disk in place within the arrel, embracing a split thimble havin screw-thread- IOO IIO

ed engagement with the barre and provided with an interior conical surface, a sleeve having a conical surface at its inner end, and a nut engaging the outer end of the sleeve. l

7. The combination with a barrel, of a plunger therein provided with a recess or cavity in its inner end, said barrel having a bore which extends through the inner end of the barrel .and has a tapered annular surface, a shell which closes the inner end of the barrel and is adapted to project into said cavity when the plunger is at the inward limit of its movement, said shell being provided at its base with a conical surface adapted to engage the conical surface in the bore, a disk inserted* in the end ofthe barrel in contact with the'iJM ner margin of said shell, a split thimble hav- 13ohaving screwlthreaded engagement with said sleeve.

' with an air- 8. The combination 'mlm a loarel,l of a lunger thereinprvided with a-recess-or cavity in its inner end, a hollow shell which closes the inner end of the barreland is a'da ted to form an air-displacin .p'roj'ectio'i'i,V said sheliY being provided at its ase with an inwardlytapered conical surface adapted t'o engage a correspondingv conical surface in the bore of the barrel, and a dislr inserted in the endjof the barel in contact with the inner -niargiifi of sad'shell and forming with the shell an airchamber, said air-chamber being connected with the air-supply passage of the tool by -means of a port extending throu h the base portion of said shell and 'tlirou'v cent part of thewall of the,barrcll 9. lhe combination with a barrel, of a lunger therein provided with a recess or cav.- lty in its inner end, `a shell for closing the inner end of the barrel and which is ada ted to project into the barrel to forni an airisplac# ing rejection, said shell being provided at its ase with an inwardl '-tapered l'conical surface adapted to anfrage a corresponding conical surface in the cbore of the barrel, a disk inserted in the bore of the barrel in contact with the inner margin of said hollow shell and a thimblev having screw-threaded enga ement with the inner end. of the barrel and caring?r on 'said plate, said barrel being provided with a controlling-valve chamber, a.

controllingevalve therein, and an ainsupply` passage communica tingwith said control j valve chamber, the base of said shell and the adjacent part of the barrel being provided ort which communicates with said air-supp y assage. c

It). The com ination with a barrel, and Aa plungertherein provided with a. recess or cavity in its inner end, said barrelhaving at its inner end an air-displacing projection adapt ed to project into said cavity in the plunger when the latter is at the inward linut of its stroke, and acontrolli valve comprising a valve-chamber 'providglfl with an Vair-supply passage, and with two admission-ports communicating with the inner end of the barrel, and two valve-pistons in saidvalyeschainber, both of which control the admission of sirto the inner end of the barrel through said admission- Y orts. f

L1. Tile combination with a`barrel and a plunger therein; of a contreiling-valve com prising a valve-chamber, twoVendwise-sliding valve-pistons located in said valve-chamber, and means for giving endwise movement to said valve-pistons, com pass es connected with the ends o said valve-c inber barrel thro and opening into the interior of the barrel by c5 ports which are uncovered when the plunger is at the outward limit of its movement, an exhaust-passage for the .inner end of the barrel which opens into the barrel through a portJlocated in position to be covered by the piston 7o before the same reaches the inward limit of its stroke, and an'adrriission; ort opening into the inner end of the barre ,and connected with the -valve-chamberbetween the inner ends of the said pistons. t. 7 5 12. The combination with a barrel and a lplunger therein, of acontrollin-valve comprising a valve-'chamber rev' ed with an airsupply passage', and with admission and exhaust ports, including two admissionsports 8o which are connected 'fwith' the b arrel by an admission-passage lwhich opens into the 1nner end o the arrel, and an exhausbport' t 'for the inner'end of .the barrel which communicates with thebarrel by` a passage opening into the barrel through a port; located at a greater distance from the inner end'of the arrel than the admission-passage, two ex'id- I` wise-sliding valve-pistons the inner .ends of which control the said two admissionfports 9o and are subject to pressure of compressed air Within the barrel in the back stroke of the plunger, and means for connecting the outer ends of said valvepchainber exterior'to the said valve-piston alternately with said airsuppljyr assag'e and with the outer air.

13V. he combination with a barrel and a plunger therein, of a controlling-valve comprising a valve-chamber with an air-supply.

passage, and with admissi'p and exhaust me ports connected with the'inner and outer ends of'th barrel the exhaust-port for the inner end of the barrel being located at a rester distance from the inner end of the arrel than the admission-port at such inner :o5

end of the barrel, two endwise-slidinrr valve Vpistons located in said valve'ehaniber, the

inner ends of said pistons bein snb'ct to pressure of air in the inner end o the' ariel,- and 'means for alternately eonnectm" the no outer ends `of said valve-chamber Wit the air-snpply passage and with the outer air Ycompi'isn'w' a passavo leading from .each end j of said va ire-chamber ando'penin into the overed by t epistcn in the outward limit 'of its movement and the other uncovered by the piston when at the inward limit of its movement, and ports leading through thev wall of the barrel to the cuter air which are :zo

prising a valve-chamber provided with a oen- Vx 25 tra] air-.admission passage communicating with an admission-port which opens intistlie inner end of the barrel, with two ports located h twoports, one of. w 'ch is un- 1 rg at opposite sides of said air admission passage and connected with an air-supply passage, with an exhaust-port communicating with the inner end of the barrel, and with an admission and exhaust port communicating with the outer end ofthe barrel, and two endwise-sliding piston-valves in said chamber7 the inner or adjacent ends of which control the passage of air from said air-supplyl passage through said admission-ports to t e admission-port leadin to the inner end of the barrel, one of whic controls the passa e of air through the exhaust-passage leadin om the inner end of. the barrel and the ot 'er of which controls the passage of air from said air-supply passage to the outer end o'fthe barrel and also controls the exhaust from the outer end of the barrel. d

15. The combination with a barrel and a plunger therein, of a controlling-valve comprisin a valve-chamber provided with a central a missionassage communicating with the ,inner end o the barrel, with two annular admission-recesses located at either side of the said central admission-passage, and communicating with an air-supply passage, said valve-chamber` also having between one of said annular admission-recesses and one end ,of the valve-chamber two annular' exhaustrecesses', one of which communicates with the inner end of the barrel .by an exhaust-port,

and the other of which communicates with the outer air and two endwise-sliding lvalvepistons in said chamber the inner ends of which control the passage of air from the said 'air-supply passage to said central admission-passage, one of said Valve-pistons having a flan e by which communication between said ex ust-recesses for the inner end of the barrel is alternately opened and closed.

16. The combination with a barrel and a plunger therein, of a controlling-valvecomprisin a valve-chamber provided with a central a missionassage communicating with the inner end o the barrel, with two annular recesses located at opposite sides of said admission-passage and communicatin with an air-supp y passage, with an annu ar recess communicating with theinner end of the barrel by an exhaust-port located at a distance from the inner end wall of the same and with an annular recess communicating by an admission -and exhaust port with the outer end of the barrel and with an annular recess communicating with the outer air, and two endwise-sliding piston-valves, the adjacent parts of which control the passage of air from said air-supply passage to said central admissionpassage, one of which controls the exhaustpassage leading from the inner end of the arrel, and the other of which controls the passage of air from said air-supply passage to the outer end of the barrel an also controls the exhaust from the outer end of the barrel, and means for connecting the 'outer ends of said valve-chamber alternately with the airsupply assage and with the outer air.

17. he combination with a barrel and a plunger therein, of a controlling-valve comprising a valve-chamber provided with a central admissionassage communicating with the inner end o` 'the barrel, with two annular recesses located at opposite sides ol said admission assage, and communicating with an air-supp y passage, with an annular recess communicating by an exhaust-port with the inner end of the barrel, and with an annular admission and exhaust passage communicating with the outer end of the barrel and two endwise-sliding piston-valves the inner or adjacent parts o which control the passage of air from the air-supply passage to said admission-ports leading to the inner end of the barrel, one of which controls the exhaust-passage leading from the inner end of the barrel, and the other of which controls the passage of air from said air-supply assage to the outer end of the barrel and allso controls the exhaust from the outer end of the barrel.

18. The combination with a barrel and a plunger therein,I ,of a controlling-valve comprisin a valve-chamber provided with a central a missionassage communicating with the inner end o the barrel, with two annular recesses located at opposite sides of said ad-- haust-recesses, one of which communicates vby an 4exhaust-port with the inner end of the barrel and the other with the outer air, said valve chamber also having between the other of said air-admission recesses and the opposite end of the barrel an annular admiss1on and exhaust recess communicati by a passage with the outer end of the barre and an adjacent annular exhaust-recess communicating with the outer air, and two, valvepistons in said chamber, the inner ends of which control th`e passage of air from said airsupply passage to said admission-ports leadin to t e inner end ofthe barrel, one of said va ve-pistons' having a ilange by which'communication between said exhaust -recesses for the inner end of the4 barrel are alternately brought into and cut ofi from communication with each other, and the other one of said pistons haying an annular flange ad apted to o en and close communication between saidv a mission and exhaust recess for the outer end of the barrel and the said exhaustrecess adjacent thereto. I

19. The combination With'a barrel Vand a 'plunger therein, of a controlling-valve comprisin a valve-chambelF provided with a centra admission assage communicating with the inner end o the barrel,l with two annular admission-recesses located at opposite sides of said admission-passage and commu- IOC IIO

nicating with the air-supnl7 nicatin end of the barrel, and an annular exhaust-re-- cessadjacent to said admission and exhaust recess cornmnmcating with the outer a1r,- and two valve-pistons 1n said chamber, the inner ends ofwh1ch control the passage of air from said air-suppl passage to the central admissionassage eading to the inner end of the barre and the outer ends of which are adapted to slide in cylindric seats in the outer ends ofv the valveschamber, one of said valve-pistons being provided with an annular flange which contro s the exhaustassages communicating with the inner en of the barrel, and the other of said valveistons being provided with a flange control ing the admission of air from the said supply-passage to the outer end of the barrel, and means for bringin the outer ends of the valve-chamber exterior to the outer ends of the valve-pistons alter# nately in communication with said air-sup-' ly passage and with the outer air, said exaust-port at'the inner end of the barrel being located at a greater distance from the inner end of the barrel than the admission-port. 20. The combination with a barrel and a plunger therein, of a valvecasing on the barrel rovided with a cylindric bore and a valvebui ing located in said chamber and 'provided with an interior valve-chamber,y said valve-bushing havin on its outer surface circumferential and ongitudinal ribs forminfr with the wall of the valve-casing a plurali ty of exteriorv spaces or chambers communicating with the inner and outer ends of the barrel, with an air-supply passage and with the outer air, said bushing being also provided with a plurality of admission and exhaust ports communicating with said exterior chambers. c

21. The combination with a barrel and a plunger therein, of a valvecasing on the barrel rovided with acylindricbore and a valvebus ing located in said chamber and provided with an interior valvechamber, said valve-bushing having o n its outer surface circumferential and longitudinal ribs formin with the wall of the valve-casing a plura ity of exterior spaces or chambers commupassave, with the interior of the barrel, ai. with t 1e outer air, said bushing being also provided with a plurality of admission and exhaust orts communicating with said exterior c ambers, and with interior annular Grooves or recesses communicating with said` admission and exhaust ports.

22. The combination with a barrel and a plunger therein, of a valve-casing attached to said barrel, a valvebushing locatedl within said casing, saidvalve-bushin being' provided With a valve-clranber'a on its cuter face with circumferential and longitudinal ribs forming with the surrounding wall of the valve-casing, a plurality of exterior chambers, including a central chamber which is in com. municatlon with the inner end of the barrel by an admission-port, a central chamber which is in communication with the air-su pply passage, two external chambers one commu'nicating with the inner end f the barrel b an exhaust-passage, andthe other with tli'e outer end of the barrel b an exhaust and admission passage and wit two chambers which communicate with the louter a'ir through exhaust-ports in the valve-casing,

said bushing also having a central admissionpassage, two annular admission-grooves located at either side of said central admissionpassage, two annular exhaust-recesses located adjacent to each other for .the exhaust from the inner end of the barrel, an-annularadznission and exhaust recess for the outer end of the barrel and an annularexhaust-recess adjacent thereto for the outer end of the barrel, and two valve-pistons in said valve-chaxn ber, the .inner ends of which are ada )ted to control the passage ol air from sai annular admission-passages to the central admissiompassage and which are provided with annular flanges controlling the exhaust from the inner end of the barrel, and the admission and exhaust from the outer end of the barrel.

23. The combination with a barrel, of a plunger therein, a valve-casing attached to.

the barrel and provided with a c lindric bore, a valve-bushin located in sai casing, capplates closing t e ends of said valve-bushing, the' said valve-casing bein@ provided at its opposite ends with screwt lreaded Ithimbles inserted 'in the o en ends thereof and bearing against the said) cap-plates, and means for holding each of said tlumbles from turning in the end of the casing, including a sleeve having a conical inner end engaging a conical inner surface on the said thimbles, and n nut having screw-threaded engagennnt with tho outer end of said sleeve and having a conical inner end adapted to engage a conical inner surface on the said thilnble, said thimblc bcing split to permit expansion of the same.

24. The combination with a barrel, and a plunger therein, said barrel boing novidcd at its base or inner end with two divergi-mt integral arms each extending outward from the barrel at an angle to the central axis thereof, and ,a handle having at its ends divergent tubular sockets in line with and adapted to receive said divergent arms.

25. The combination 'with a barrel, and a plunger therein, said barrel being provided at its base or inner` end with two integral Ilo arms each extendin at an angle to the cen- 1 my invention I afiix my signature, in. restrai axis of the barre and a handle having at ence of two witnesses, this 23d day o Auits ends sockets adapted for detachable engust, A. D. 1904.

gagement with said arms, one of said sockets i AXEL LEVEDAHL. 5 having a detaohably-seored separable seo- Witnesses: Y

tion. v W. H. PENN,

In testimony that I claiin the foregoing as CARRIE MUSCHLER. 

